In recent years, wireless local area networks (LANs) have spread with development of communication technologies. In addition, with the wireless LANs, products corresponding to the wireless LANs (hereinafter also referred to as wireless communication devices) have also increased. When wireless communication devices increase, there is a high possibility of communication efficiency deteriorating. Therefore, it is desirable to improve the communication efficiency.
One reason for deteriorating communication efficiency of wireless communication is collision of frames (packets). For example, when a plurality of wireless communication devices simultaneously transmit frames, frames collide. Thus, there is a low possibility of the frames being successfully received. As a result, the colliding frames are retransmitted, thereby deteriorating communication efficiency.
In contrast, the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard provides a mechanism such as a request to send (RTS)/clear to send (CTS) scheme. Specifically, when a wireless communication device of a data transmission source transmits an RTS frame as a data transmission request and receives a CTS frame as a confirmation notification from a wireless communication device of a data transmission destination, data transmission starts. On the other hand, a wireless communication device receiving at least one of the RTS frame and the CTS frame sets a transmission stop period in which transmission of the self-device stops only for a data transmission period based on an RTS/CTS procedure. For example, the transmission stop period is called a network allocation vector (NAV) period. Thus, collision of frames is avoided.
In addition, Patent Literature 1 proposes the disclosure related to a scheme in which a change occurs in conformity with the RTS/CTS scheme. Specifically, when a wireless communication device receives an RTS frame, the wireless communication device sets NAV1 on the basis of a legacy-signal (L-SIG) duration. Then, in a case in which a frame from a transmission source of the RTS frame is not detected within a period in which a predetermined period is added to NAV1, the wireless communication device cancels NAV2 based on a media access control (MAC) duration and starts transmission.